I found a bunch of them for cheap on eBay, as I am in the market for a relatively cheap hone for touching up my edge. It's not dull yet. I just want to have something handy for when it gets a little grabby. After a very little bit of initial research, I've read that I'd be better off buying a brick. Has anyone used/heard of these things, and are they as bad as the general sentiment about them seems to be?